JP2009195066A - Power supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply device that has excellent heat-dissipation properties while using a heat-transfer member. <P>SOLUTION: The power supply device has a power supply body (21), a liquid heat-exchange medium (3) in contact with the power supply body for executing heat exchange with the power supply body, a case (10) for storing the power supply body and the heat-exchange medium therein, and a heat-transfer member (60) mounted onto the outer face of the case while having a higher heat conductivity than that of outer air in contact with the case. The heat-transfer member has each curved part protruding toward the case, to transfer the heat from the case via the curved part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat dissipation structure in a power supply device.

  Some conventional vehicles include a battery pack in which a plurality of single cells are housed in a case. This vehicle is called a so-called hybrid vehicle, and uses the output of the battery pack to drive the vehicle or charge the battery pack with regenerative energy of the vehicle.

  Here, it is known that a single battery generates heat by charging and discharging. Therefore, in order to improve the heat dissipation of the unit cell, there is one in which fins are provided on the outer surface of the case (see, for example, Patent Document 1).

In the battery device described in Patent Document 1, a plurality of single cells and insulating oil are accommodated inside the case, and a plurality of fins are formed on the outer surface of the case. In this configuration, the heat generated in the single cell is transmitted to the case via the insulating oil and released into the atmosphere via the case. And by forming a plurality of fins on the outer surface of the case, the surface area of the case is increased to improve the heat dissipation of the case, in other words, the heat dissipation of the single cell.
JP-A-10-199497 (paragraph 0016, FIG. 3)

  Here, in the configuration in which the fin is provided on the outer surface of the case, the fin is generally formed integrally with the case. However, when molding a case integrally provided with fins, the material of the case may be limited to a specific material (for example, aluminum) for molding reasons. Here, since aluminum is expensive, it is difficult to reduce the cost of the power supply device.

  The present invention includes a power source that outputs electric power, a liquid heat exchange medium that contacts the power source and performs heat exchange with the power source, and a case that houses the power source and the heat exchange medium. A heat transfer member attached to the outer surface of the case and having a higher thermal conductivity than the outside air in contact with the case. The heat transfer member has a bent portion that protrudes toward the case, and allows heat transfer from the case through the bent portion.

  Here, an adjustment mechanism for adjusting the pressing force of the heat transfer member with respect to the case can be provided. Thereby, the pressing force of the heat transfer member against the case can be easily adjusted. Moreover, cost can be reduced compared with the case where a case and a heat-transfer member are attached by welding.

  Specifically, the pressing force of the heat transfer member against the case can be adjusted by fixing the adjustment mechanism to the case and changing the position where the adjustment mechanism is engaged with the heat transfer member. That is, one end of the heat transfer member is fixed to the case, the other end of the heat transfer member is engaged with the adjustment mechanism, and the other end of the heat transfer member is moved by the adjustment mechanism to adjust the pressing force. can do. Further, both ends of the heat transfer member can be engaged with the adjustment mechanism.

  On the other hand, the area | region which opposes a heat transfer member among the outer surfaces of a case can be formed in the shape which becomes convex toward the outer side of a case. For example, in a region facing the heat transfer member, a curved surface portion that protrudes toward the outside of the case can be provided. By comprising in this way, a heat transfer member can be made easy to arrange | position along the outer surface of a case.

  In the power supply device of the present invention, the bent portion of the heat transfer member can be brought into direct contact with the outer surface of the case. Further, an elastic member that allows heat transfer between the case and the heat transfer member may be disposed between the case and the heat transfer member. By using this elastic member, the elastic member can be easily brought into contact with the case, the heat transfer member can be easily brought into contact with the elastic member, and heat transfer between the case and the heat transfer member can be efficiently performed. Can do.

  In addition, the power supply device of this invention can be mounted in a vehicle. Moreover, as a power supply body, secondary batteries, such as a nickel metal hydride battery and a lithium ion battery, can be used, for example.

  According to the present invention, by using the heat transfer member, the heat dissipation of the case, in other words, the heat dissipation of the power supply body can be improved. That is, by attaching the heat transfer member to the outer surface of the case, the surface area of the outer surface of the case can be increased, and the heat dissipation of the case can be improved.

  Moreover, in this invention, since the heat transfer member used for heat radiation is comprised separately from the case, a heat transfer member can be formed with a material different from a case. That is, the material of the heat transfer member can be appropriately set in consideration of the heat dissipation of the power supply device. In addition, the case can be easily manufactured at low cost compared to the case where the fins used for heat dissipation are formed integrally with the case.

  Examples of the present invention will be described below.

  The configuration of the battery pack (power supply device) in Embodiment 1 of the present invention will be described with reference to FIGS. Here, FIG. 1 is an external view showing the configuration of the battery pack, and FIG. 2 is a cross-sectional view showing the internal configuration of the battery pack. The battery pack of this embodiment is mounted on a vehicle. And a vehicle can be drive | worked using the output of a battery pack, or the regenerative energy of a vehicle can be charged to a battery pack.

  The battery pack 1 of this embodiment includes a case 10 and a battery unit 20 accommodated in the case 10. The case 10 includes a housing member 11 that forms a space for housing the battery unit 20, and a lid member 12 that covers the opening of the housing member 11. The lid member 12 is fixed to the housing member 11 by a fastening member such as a screw or is fixed by welding. Thereby, the inside of case 10 will be in a sealed state.

  The housing member 11 and the lid member 12 are formed of a material having excellent thermal conductivity, corrosion resistance, etc., for example, a material having a thermal conductivity equal to or higher than that of the heat exchange medium 3 described later. be able to. Specifically, the housing member 11 and the lid member 12 can be formed of a metal such as aluminum or iron.

  As shown in FIGS. 1 and 2, the bottom surface portion 11 a of the housing member 11 is configured by a curved surface that is convex toward the outside of the battery pack 1. The curvature of the curved surface at the bottom surface portion 11a can be set as appropriate. In addition, the bottom face part 11a can also be comprised by a substantially flat surface. However, the strength of the housing member 11 can be improved by configuring the bottom surface portion 11a with a curved surface rather than configuring it with a flat surface.

  Further, the bottom surface portion 11a can be formed in a shape having a step along the curved surface without being formed on the curved surface. That is, the bottom surface portion 11a can be constituted by a plurality of step portions. Also in this case, the bottom surface portion 11 a is convex toward the outside of the battery pack 1.

  Here, in addition to the battery unit 20, a heat exchange medium 3 for performing heat exchange with the battery unit 20 is accommodated in the case 10. Specifically, the heat exchange medium 3 is in contact with the surface of the battery unit 20 and is in contact with the inner wall surface of the case 10. As will be described later, the heat exchange medium 3 is used to adjust the temperature of the battery unit 20.

  The heat exchange medium 3 is an insulating liquid, and for example, an insulating oil or a fluorine-based inert liquid can be used. As the fluorine-based inert liquid, for example, Fluorinert, Novec HFE (hydrofluoroether), and Novec 1230 (manufactured by 3M) can be used.

  In addition, if the surface of the battery unit 20 is insulated, it is not necessary to use an insulating liquid as the heat exchange medium 3. For example, an insulating film can be formed on the surface of the battery unit 20, and in this case, a non-insulating heat exchange medium such as water can be used.

  On the other hand, the battery unit 20 is obtained by electrically connecting a plurality of single cells (secondary batteries as power supply bodies) 21. The plurality of single cells 21 are arranged in parallel inside the case 10.

  Each unit cell 21 is supported by a pair of plate-like support members (not shown) at both ends. These supporting members are fixed to the case 10 (accommodating member 11) by fastening members (not shown) such as screws. In this embodiment, two support members are used, but these support members may be configured as a single unit.

  In addition, positive and negative terminals (not shown) are provided at both ends of each unit cell 21. The terminals of each unit cell 21 are connected to the terminals of other unit cells 21 arranged adjacent to each other through a bus bar (not shown). That is, a desired high output (for example, 200 [V]) can be obtained as the battery unit 20 by electrically connecting the plurality of single cells 21 in series via the bus bar.

  Here, positive two and negative electrode wirings (not shown) are connected to two specific single cells 21 among the plurality of single cells 21, and these wirings penetrate the case 10 to form a case. 10 is connected to an electronic device arranged outside. Thereby, an electronic device can be driven using the output of the battery unit 20. Any electronic device may be used as long as it operates by receiving power supply. For example, a converter for converting the voltage value of the battery unit 20 or an inverter for supplying power to a motor used for running the vehicle. Etc.

  As the cell 21, a secondary battery such as a nickel metal hydride battery or a lithium ion battery can be used. Instead of the secondary battery, an electric double layer capacitor (capacitor) or a fuel cell as a power source can be used. Further, in this embodiment, the cylindrical unit cell 21 is used, but a unit cell having another shape such as a square unit can also be used.

  On the other hand, a stud bolt 41 is fixed to the side surface portion 11 b of the housing member 11. A nut 42 is engaged with the stud bolt 41. An adjustment unit 50 is fixed to the side surface portion 11c facing the side surface portion 11b. The adjustment unit 50 is fixed to the housing member 11 by fastening members such as bolts or welding. The adjustment unit 50 includes an outer case 51 and a bolt 52 that is rotatably supported with respect to the outer case 51.

  The fin member (heat transfer member) 60 is formed by bending a plate-like member, and is disposed along the outer surface of the housing member 11. The fin member 60 is made of a material having a higher thermal conductivity than the gas (air) in contact with the case 10. Specifically, the fin member 60 can be formed of a metal such as aluminum or iron.

  One end portion 60 a of the fin member 60 is disposed along the side surface portion 11 b of the housing member 11. Further, an opening is formed in one end 60a of the fin member 60, and the stud bolt 41 penetrates through the opening. With the stud bolt 41 passing through the opening of the fin member 60, the nut 42 is fastened to the stud bolt 41, thereby fixing the one end portion 60 a of the fin member 60 to the housing member 11.

  On the other hand, the other end portion 60 b of the fin member 60 is disposed along the side surface portion 11 c of the housing member 11. Further, as shown in FIG. 3, a plurality of openings 61 are formed in the other end portion 60 b of the fin member 60. Here, FIG. 3 is a view when the other end portion 60b of the fin member 60 is viewed from the front. As shown in FIG. 4, a screw part 52 a is formed on the outer peripheral surface of the bolt 52, and a part of the screw part 52 a is engaged with the opening 61 of the fin member 60.

  Here, when the bolt 52 is rotated, the engagement position of the screw part 52a and the opening part 61 changes. That is, by rotating the bolt 52, the fin member 60 can be moved in the direction indicated by the arrow X1 in FIG. Specifically, the fin member 60 can be moved downward with respect to the bolt 52 by rotating the bolt 52 in one direction. Further, by rotating the bolt 52 in the other direction, the fin member 60 can be moved in the upward direction in FIG.

  On the other hand, as shown in FIGS. 1 and 2, in the fin member 60, a curved surface portion (bending portion) 60 c that is convex toward the housing member 11 and a curved surface that is convex toward the opposite side of the housing member 11. The portions 60d are alternately and continuously formed. In the present embodiment, a plurality of curved surface portions 60c are formed, but only one curved surface portion 60c may be formed.

  An elastic sheet (elastic member) 70 is disposed between the fin member 60 (curved surface portion 60 c) and the bottom surface portion 11 a of the housing member 11. The elastic sheet 70 is fixed to the bottom surface portion 11 a in a state along the outer surface of the bottom surface portion 11 a, and comes into contact with the bottom surface portion 11 a and the curved surface portion 60 c of the fin member 60. The elastic sheet 70 is a material having a thermal conductivity higher than that of the gas (air) in contact with the case 10 and is made of an elastically deformable material. For example, the elastic sheet 70 can be formed by dispersing a material having a higher thermal conductivity than air in an elastically deformable material (resin material).

  In this embodiment, the elastic sheet 70 is used, but the elastic sheet 70 may not be used. That is, the fin member 60 (curved surface portion 60 c) can be directly brought into contact with the bottom surface portion 11 a of the housing member 11.

  Here, by using the elastically deformable elastic sheet 70, the elastic sheet 70 can be easily attached along the bottom surface portion 11a, and the fin member 60 can be easily brought into contact with the elastic sheet 70. That is, when it is difficult to bring the fin member 60 into direct contact with the bottom surface portion 11 a, the heat transfer between the housing member 11 and the fin member 60 can be efficiently performed by using the elastic sheet 70.

  In the configuration described above, when the other end 60b of the fin member 60 is moved by the rotation of the bolt 52, the pressing force (contact pressure) of the fin member 60 against the elastic sheet 70 can be adjusted. That is, if the bolt 52 is rotated in one direction, the fin member 60 can be loosened, and if the bolt 52 is rotated in the other direction, the fin member 60 can be tightened.

  Thereby, the fin member 60 can be reliably brought into contact with the elastic sheet 70 by the operation of the bolt 52. Here, by loosening or tightening the fin member 60 with respect to the elastic sheet 70, the shapes of the curved surface portions 60c and 60d in the fin member 60 change. That is, the curvature in the curved surface portions 60c and 60d changes.

  In the battery pack 1 of the present embodiment, when the unit cell 21 generates heat by charging and discharging, the heat generated in the unit cell 21 is exchanged with the heat exchange medium 3 in contact with the unit cell 21, It is transmitted to the heat exchange medium 3. The heat exchange medium 3 reaches the case 10 by flowing inside the case 10 and transfers heat to the case 10.

  Here, if a stirring member (fan or the like) for forcibly flowing the heat exchange medium 3 is arranged inside the case 10, the heat of the unit cell 21 is efficiently transferred to the case 10 via the heat exchange medium 3. It can be transmitted well.

  The heat transmitted to the case 10 is released to the outside (in the atmosphere) of the case 10 or is transmitted to the fin member 60 via the elastic sheet 70 that contacts the case 10. Here, since the elastic sheet 70 and the fin member 60 are formed of a material having a higher thermal conductivity than the atmosphere (air) in contact with the case 10, the heat transferred to the case 10 is mainly the elastic sheet. It is transmitted to the fin member 60 through 70.

  In this way, by transferring the heat transferred to the case 10 to the fin member 60, the heat dissipation of the case 10 can be improved. In other words, the heat dissipation of the unit cell 21 can be improved.

  Here, if air is guided to the fin member 60 using a fan or the like, the heat dissipation of the fin member 60 can be improved. Thereby, the heat dissipation of the cell 21 can be further improved. In this case, if a protrusion that contacts the air guided to the fan member 60 is formed in a part of the fin member 60, the protrusion can cause a turbulent flow in the air flow. Thereby, the heat transfer between the fin member 60 and air can be improved. Instead of guiding air to the fin member 60, a gas or liquid having a component different from that of air may be guided. These gases and liquids serve as heat exchange media for performing heat exchange with the fin member 60.

  In addition, according to the present embodiment, it is not necessary to form the case 10 in a complicated shape as in the conventional configuration (case in which fins are integrally provided). Thereby, the range of selection about the material of case 10 can be expanded.

  Specifically, in the conventional configuration, it is common to mold by aluminum die casting, but the material of the case 10 of this embodiment is not an expensive material such as aluminum but an inexpensive iron or the like. Can do. If iron is used as the material of the case 10, the case 10 (the housing member 11 and the lid member 10) can be manufactured by press molding, and mass productivity can be improved. In addition, by using iron, the thickness of the case 10 can be reduced while securing the strength of the case 10.

  Further, in the present embodiment, since the bottom surface portion 11a is formed in a shape that protrudes toward the outside of the battery pack 1, both end portions 60a, 60b of the fin member 60 are formed on the side surface portions 11b, 11c of the housing member 11. In the attached configuration, the fin member 60 (curved surface portions 60c and 60d) can be easily arranged along the bottom surface portion 11a. Thereby, the fin member 60 can be efficiently pressed against the bottom surface portion 11 a of the housing member 11.

  Furthermore, in the case where the curved surface portion 60c of the fin member 60 is brought into contact with the case 10, the configuration of this embodiment can reduce the manufacturing cost as compared with the case where the curved surface portion 60c and the case 10 are welded. That is, in this embodiment, the stud bolt 41 and the adjustment unit 50 are used so that the curved surface portion 60c of the fin member 60 only needs to be in contact with the case 10, and the curved surface portion 60c is fixed to the case 10 by welding. There is no need to keep it.

  In the present embodiment, the fin member 60 is constituted by a plate-like member, but is not limited to this. That is, the fin member 60 can also be comprised by a linear member. However, the contact area with the elastic sheet 70 or the case 10 can be ensured by configuring the fin member 60 with a plate-like member.

  In the present embodiment, one end portion 60a of the fin member 60 is fixed to the housing member 11 via the stud bolt 41, and the other end portion 60b of the fin member 60 can be adjusted by the adjustment unit 50. It is not a thing. Specifically, the adjustment unit 50 may be disposed with respect to both end portions 60a and 60b of the fin member 60, and the both end portions 60a and 60b of the fin member 60 may be moved.

  Furthermore, in this embodiment, the pressing force of the fin member 60 against the elastic sheet 70 is adjusted by using the adjusting unit 50 shown in FIGS. 3 and 4, but the present invention is not limited to this. That is, as long as at least one end of the fin member 60 is moved, the pressing force of the fin member 60 against the elastic sheet 70 can be adjusted.

  For example, as another configuration for adjusting the pressing force of the fin member 60, the configuration shown in FIG. Here, FIG. 5 is a schematic diagram illustrating a partial configuration of a battery pack that is a modification of the present embodiment, and is a diagram illustrating a configuration in which the position of one end of the fin member is changed. In addition, the same code | symbol is used about the member which has the same function as the member demonstrated in the Example mentioned above.

  In FIG. 5, the end portion 60 b of the fin member 60 is bent so as to be substantially parallel to the flange portion 11 d formed on the housing member 11. And the bolt 80 is being fixed to the edge part 60b of the fin member 60 so that rotation is possible. The screw part 80a of the bolt 80 is engaged with a screw hole part 90 provided in the flange part 11d.

  In the configuration shown in FIG. 5, when the bolt 80 is rotated, the engagement position of the screw portion 80a with respect to the screw hole portion 90 changes. Accordingly, the distance between the flange portion 11d and the end portion 60b of the fin member 60 (the interval in the vertical direction in FIG. 5) changes.

  That is, by rotation of the bolt 80, the end portion 60b of the fin member 60 moves in the direction indicated by the arrow X2 in FIG. 5 with respect to the flange portion 11d. Specifically, the end 60b can be moved closer to the flange 11d by rotating the bolt 80 in one direction, and the end 60b is separated from the flange 11d by rotating the bolt 80 in the other direction. Can do.

  By moving the end portion 60b of the fin member 60 in this manner, the pressing force of the fin member 60 against the elastic sheet 70 can be adjusted as in the first embodiment.

  On the other hand, in the embodiment described above, the pressing force of the fin member 60 is adjusted using the adjustment unit 50, but the fin member 60 may be fixed to the case 10 in advance. That is, both end portions 60 a and 60 b of the fin member 60 can be fixed to the case 10.

  Here, the configuration for fixing the fin member 60 to the case 10 may be any configuration. For example, as described in the above-described embodiments, both end portions 60a and 60b of the fin member 60 can be fixed to the housing member 11 using stud bolts and nuts. Further, both end portions 60 a and 60 b of the fin member 60 can be fixed by being sandwiched between the housing member 11 and the lid member 12.

  Specifically, as shown in FIG. 6, the end portion 60 b of the fin member 60 is disposed between the flange portion 11 d of the housing member 11 and the flange portion 12 a of the lid member 12. In this state, the end portion 60b and the flange portions 11d and 12a can be fixed together using bolts or the like. Further, in the state shown in FIG. 6, the end portion 60b and the flange portions 11d and 12a are bent in the direction indicated by the arrow A, in other words, the end portion 60b and the flange portions 11d and 12a are folded, thereby The member 60 can be fixed to the case 10.

  On the other hand, in this embodiment, the fin member 60 is disposed on the bottom surface portion 11a side of the housing member 11, but the present invention is not limited to this. That is, the curved surface portions 60c and 60d of the fin member 60 are disposed along the side surface portion of the housing member 11, or the fin member 60 (curved surface portions 60c and 60d) is disposed along the upper surface portion of the lid member 12. can do.

  Moreover, as shown in FIG. 7, the fin member 60 can also be arrange | positioned so that the circumference | surroundings of case 10 may be enclosed. In the fin member 60 shown in FIG. 7, curved surface portions 60 c and 60 d are alternately and continuously formed around the case 10. The curved surface portion 60c of the fin member 60 is in contact with the upper surface portion of the case 10, two side surface portions facing each other, and the bottom surface portion. In this configuration, at least a part of the fin member 60 may be fixed to the case 10 using the stud bolt 41 described in the first embodiment.

  Further, in the configuration shown in FIG. 7, the fin member 60 is continuously formed around the case 10. However, the fin member 60 is provided with two end portions, and the engagement positions at these end portions are changed. You can also. In this case, the pressing force of the fin member 60 on the case member 10 can be changed by changing the engagement positions at both ends of the fin member 60. Note that the entire outer surface of the case 10 may be covered with the fin member 60.

  Furthermore, in the embodiment described above, the curved surface portions 60c and 60d are formed on the fin member 60, but the present invention is not limited to this. That is, the fin member 60 may have any shape as long as it has a portion that contacts the elastic sheet 70 or the case 10 and a portion that is separated from the elastic sheet 70 or the case 10. Specifically, the fin member 60 in contact with the case 10 can have a shape shown in FIG.

  The configuration shown in FIG. 8 is the same as the above-described embodiment in that the fin member 60 has a convex portion toward the case 10, but the tip of the convex portion has a flat surface. This is different from the embodiment described above. In this configuration, the contact area between the fin member 60 and the case 10 can be increased.

It is the schematic which shows the external structure of the battery pack which is Example 1 of this invention. 1 is a schematic diagram illustrating an internal configuration of a battery pack that is Embodiment 1. FIG. It is a front view which shows the edge part of a fin member. It is the schematic which shows the structure of an adjustment unit. 6 is a schematic view showing a partial configuration of a battery pack that is a modification of Example 1. FIG. 6 is a schematic diagram showing a partial configuration of a battery pack that is another modification of Example 1. FIG. FIG. 6 is a schematic diagram illustrating a configuration of a battery pack that is another modification of Example 1; It is the schematic which shows the shape of a fin member.

Explanation of symbols

1: Battery pack (power supply)
10: Case 21: Single battery (power supply)
3: Heat exchange medium 50: Adjustment unit (adjustment mechanism)
52: Bolt 60: Fin member (heat transfer member)
60c: curved surface portion (bending portion)
70: Elastic sheet (elastic member)

Claims (7)

A power supply that outputs power;
A liquid heat exchange medium in contact with the power supply and for exchanging heat with the power supply;
A case for housing the power supply body and the heat exchange medium;
A heat transfer member attached to the outer surface of the case and having a higher thermal conductivity than the outside air in contact with the case;
The heat transfer member has a bent portion that protrudes toward the case, and allows heat transfer from the case through the bent portion.   The power supply device according to claim 1, further comprising an adjustment mechanism for adjusting a pressing force of the heat transfer member with respect to the case.   The power supply apparatus according to claim 2, wherein the adjustment mechanism is fixed to the case and adjusts the pressing force by changing a position where the adjustment mechanism is engaged with the heat transfer member.   The area | region which opposes the said heat transfer member among the outer surfaces of the said case is formed in the shape which becomes convex toward the outer side of the said case, The Claim 1 characterized by the above-mentioned. Power supply.   5. The power supply device according to claim 4, wherein an outer surface of the case has a curved surface portion that protrudes toward the outside of the case in a region facing the heat transfer member.   The power supply device according to any one of claims 1 to 5, wherein a bent portion of the heat transfer member is in contact with an outer surface of the case. 6. The elastic member according to claim 1, further comprising an elastic member that is disposed between the case and the heat transfer member and allows heat transfer between the case and the heat transfer member. Power supply.

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